if you look at the aggro meter itself, its pretty easy to see how good the tank is doing in terms of aggro, even dps is pulling off the tank sure there are a number of things that could be happening there, but if the dps is pulling off the tank AND the healer....someone isn't pressing their instant get hate button enough.

They should macro it for best results.

/ac "Claim"
/ac "Get Hate" <t>
/ac "laugh Out Loud" <t>
/"Manderville Dance"
/Win motion

best hate generating macro iv seen for WAR and PLD pulls. not even those pesky ilvl150 blm can hang.